Julius Rosenwald wasn’t the only one keeping an eye on Ed Gertz.Concurrently, Chicago was in the midst of bitter Taxi Wars. The taxi business was still developing, wholly unregulated, and competition amongst growing cab companies and independents was fierce, endangering drivers, riders and pedestrians who had to dodge the pack of cabs that would descend upon potential fares en mass with contesting drivers invariably getting into fights. Poppy supplemented his income working as a schtarker – muscle - for John D. Hertz, whose Yellow Cab company was asserting dominance.In his youth, Hertz (b. Sandor Herz, Slovakian Jew) hung out in...